Kimberly and Irene collected buttons. Irene gave 70% of her buttons to Kimberly. As a result, Kimberly's buttons increased by 20%. If Kimberly had 126 buttons left, find the total number of buttons the two girls had at first.
| |
Comparing the change
in Irene's buttons |
Irene |
Kimberly |
| Before |
10x1 =
10 u |
|
5x7 =
35 u |
| Change |
- 7x1 =
- 7 u |
- 1x7 =
- 7 u |
+ 1x7 =
+ 7 u |
| After |
3x1 =
3 u |
|
6x7 =
42 u |
70% =
70100 =
710 20% =
20100 =
15 The number of buttons that Kimberly gave to Irene is repeated. Make the number of buttons that Kimberly gave to Irene the same. LCM of 1 and 7 is 7.
Number of buttons that Kimberly had in the end = 42 u
42 u = 126
1 u = 126 ÷ 42 = 3
Number of buttons that Irene and Kimberly had at first
= 10 u + 35 u
= 45 u
= 45 x 3
= 135
Answer(s): 135
